1. Technical Field of the Invention
The present invention generally relates to optical networks. More particularly, and not by way of any limitation, the present invention is directed to a system and method for discovering wavelengths in network elements having an optical architecture.
2. Description of Related Art
Optical networks are high-capacity telecommunications networks comprised of optical and opto-electronic technologies and components, and provide wavelength-based services in addition to signal routing, grooming, and restoration at the wavelength level. These networks, based on the emergence of the so-called optical layer operating entirely in the optical domain in transport networks, can not only support extraordinary capacity (up to terabits per second (Tbps)), but also provide reduced costs for bandwidth-intensive applications such as the Internet, interactive video-on-demand and multimedia, and advanced digital services.
Of the several key enabling technologies necessary for the successful deployment of optical networks, dense wavelength division multiplexing (DWDM) is of particular significance. DWDM is a fiber-optic transmission technique that increases the capacity of embedded fiber by first assigning incoming optical signals to specific wavelengths within a designated frequency band (e.g., channels separated by sub-nanometer spacing) and then multiplexing the resulting signals out onto a single fiber. By combining multiple optical signals using DWDM, they can be amplified as a group and transported over a single fiber to increase capacity in a cost-effective manner. Each signal carried can be at a different rate (e.g., Optical Carrier (OC)-3, OC-12, OC-48, etc.) and in a different format (e.g., Synchronous Optical Network (SONET) and its companion Synchronous Digital Hierarchy (SDH), Asynchronous Transfer Mode (ATM), Internet Protocol (IP) data, etc.). The forwarded optical signals are transported over fiber optic cables supported by network elements, such as terminal multiplexers and add/drop multiplexers, that provide network operations functionalities and transport network functions such as adding, dropping, regenerating, and permitting the passage of wavelengths.
Many of the maintenance operations associated with the optical network involve field operation technicians, i.e., “craftpersons” or “crafts,” interfacing with network elements via terminals. Prior to commencing maintenance operations on a network element, which may involve taking the network element off-line, the craft must have an understanding of how the network element affects other network elements so that data transmissions will not be corrupted or interrupted. In this regard, it is critical to have an indication of the passthrough traffic in the network element. In exist ing optical networks, crafts consult a manual record of the optical network layout in order to account for passthrough wavelengths. Typically, these records are stored in a network management database, spreadsheet or handwritten logbook. These records may not be co-located with the network element and may not be readably accessible to the craft during maintenance operations. Moreover, the records may be stale or contain errors due to the manual upkeep associated with the records.